Input file generation
Yambo generates its own input files: you just tell the code what you want to calculate by launching Yambo along with one or more lowercase options. (Uppercase options are considered in the following section).
To see the list of runlevels and options, run yambo -h or better,
$ yambo -H
Tool: yambo 4.1.2 rev.14024
Description: A shiny pot of fun and happiness [C.D.Hogan]
[Upper case options]
-i :Initialization
-o <opt> :Optics [opt=(c)hi is (G)-space / (b)se is (eh)-space ]
-k <opt> :Kernel [opt=hartree/alda/lrc/hf/sex]
-y <opt> :BSE solver [opt=h/d/(p/f)i]
(h)aydock/(d)iagonalization/(i)nversion
-r :Coulomb potential
-x :Hartree-Fock Self-energy and local XC
-d :Dynamical Inverse Dielectric Matrix
-b :Static Inverse Dielectric Matrix
-p <opt> :GW approximations [opt=(p)PA/(c)HOSEX]
-g <opt> :Dyson Equation solver
[opt=(n)ewton/(s)ecant/(g)reen]
-l :GoWo Quasiparticle lifetimes
-a :ACFDT Total Energy
Note that multiple options can be used together (in some cases this is actually a necessity). For instance:
yambo -o c -k hartree Calculate optical spectra including local field effects (Hartree approximation) yambo -x -g n -p p Perform a Hartree-Fock and GW calculation using a plasmon-pole approximation
After launching Yambo with a lowercase option, Yambo will generate an appropriate input file (default name: yambo.in) and launch the vi editor. (This can be changed at configure). Yambo will also read various parameters from existing database files and/or input files and use them to suggest values to use. For instance, for bulk hBN, yambo -b will generate an input file suggesting a range of bands:
% BndsRnXd 1 | 100 | # [Xd] Polarization function bands %
because the core databases (defined by the DFT run) were made with 100 bands. If a smaller range is defined by the user and the calculation launched, Yambo will read from any new database and suggest this smaller range the next time an input file is generated.